Boolean options not under specific compile flags (with default values in []):
(You can learn which options exist in your version by checking your current
option setting, which is reached via the 'O' cmd.)

autodig        dig if moving and wielding digging tool            [FALSE]
autopickup     automatically pick up objects you move over        [TRUE]
autoquiver     when firing with an empty quiver, select some
               suitable inventory weapon to fill the quiver       [FALSE]
BIOS           allow the use of IBM ROM BIOS calls                [FALSE]
cmdassist      give help for errors on direction & other commands [TRUE]
confirm        ask before hitting tame or peaceful monsters       [TRUE]
DECgraphics    use DEC/VT line-drawing characters for the dungeon [FALSE]
eight_bit_tty  send 8-bit characters straight to terminal         [FALSE]
extmenu        use a menu for selecting extended commands (#)     [FALSE]
fixinv         try to retain the same letter for the same object  [TRUE]
help           print all available info when using the / command  [TRUE]
IBMgraphics    use IBM extended characters for the dungeon        [FALSE]
ignintr        ignore interrupt signal, including breaks          [FALSE]
legacy         print introductory message                         [TRUE]
lit_corridor   show a dark corridor as lit if in sight            [FALSE]
lootabc        use a/b/c rather than o/i/b when looting           [FALSE]
mail           enable the mail daemon                             [TRUE]
null           allow nulls to be sent to your terminal            [TRUE]
               try turning this option off (forcing NetHack to use its own
               delay code) if moving objects seem to teleport across rooms
perm_invent    keep inventory in a permanent window               [FALSE]
pickup_thrown  override pickup_types for thrown objects           [TRUE]
pushweapon     when wielding a new weapon, put your previously
               wielded weapon into the secondary weapon slot      [FALSE]
rawio          allow the use of raw I/O                           [FALSE]
rest_on_space  count the space bar as a rest character            [FALSE]
safe_pet       prevent you from (knowingly) attacking your pet(s) [TRUE]
showrace       show yourself by your race rather than by role     [FALSE]
silent         don't use your terminal's bell sound               [TRUE]
sortpack       group similar kinds of objects in inventory        [TRUE]
sound          enable messages about what your character hears    [TRUE]
               (note: this has nothing to do with your computer's audio
               capabilities, and the game resets it periodically)
sparkle        display sparkly effect for resisted magical        [TRUE]
               attacks (e.g. fire attack on fire-resistant monster)
standout       use standout mode for --More-- on messages         [FALSE]
time           display elapsed game time, in moves                [FALSE]
tombstone      print tombstone when you die                       [TRUE]
toptenwin      print topten in a window rather than stdout        [FALSE]
travel         enable the command to travel to a map location via [TRUE]
               a shortest-path algorithm, usually invoked by '_'.
use_inverse    display detected monsters in highlighted manner    [FALSE]
verbose        print more commentary during the game              [TRUE]



There are further boolean options controlled by compilation flags.

Boolean option if INSURANCE was set at compile time:
checkpoint save game state after each level change, for possible  [TRUE]
           recovery after program crash

Boolean option if NEWS was set at compile time:
news       print any news from game administrator on startup      [TRUE]

Boolean option if MFLOPPY was set at compile time:
checkspace check free disk space before writing files to disk     [TRUE]

Boolean option if EXP_ON_BOTL was set at compile time:
showexp    display your accumulated experience points             [FALSE]

Boolean option if SCORE_ON_BOTL was set at compile time:
showscore  display your approximate accumulated score             [FALSE]

Boolean options if TEXTCOLOR was set at compile time:
color      use different colors for objects on screen   [TRUE for micros]
hilite_pet display pets in a highlighted manner                   [FALSE]

Boolean option if TIMED_DELAY was set at compile time (tty interface only):
timed_delay    on unix and VMS, use a timer instead of sending
               extra screen output when attempting to pause for
               display effect.  on MSDOS without the termcap
               lib, whether or not to pause for visual effect.    [TRUE]

Boolean option for Amiga, or for others if ALTMETA was set at compile time:
altmeta        For Amiga, treat Alt+key as Meta+key.              [TRUE]
altmeta        For unix and VMS, treat two character sequence
               "ESC c" as M-c (Meta+c, 8th bit set) when nethack
               obtains a command from player's keyboard.          [FALSE]

Boolean option if USE_TILES was set at compile time (MSDOS protected mode only):
preload_tiles  control whether tiles get pre-loaded into RAM at the
               start of the game.  Doing so enhances performance
               of the tile graphics, but uses more memory.        [TRUE]

Any Boolean option can be negated by prefixing it with a '!' or 'no'.


Compound options are written as option_name:option_value.

Compound options which can be set during the game are:

boulder       override the default boulder symbol with another default: [`]
disclose      the types of information you want offered at the end of the
              game  [ni na nv ng nc no]
fruit         the name of a fruit you enjoy eating  [slime mold]
              (basically a whimsy which NetHack uses from time to time).
menustyle     user interface for selection of multiple objects:
              Traditional -- one object at a time prompting;
              Combination -- prompt for classes of interest, then menu;
              Partial     -- skip class prompt, use menu of all objects;
              Full        -- menu for classes of interest, then object menu;
              only the first letter ('T','C','P','F') matters; 'N' (None)
              is a synonym for 'T', as is boolean style negation  [Full]
number_pad    alphabetic versus numeric control over movement:
               0 -- traditional hjkl + yubn movement (default);
               1 -- digits control movement, for use with numeric keypad;
               2 -- same as 1, but '5' works as 'g' prefix rather than 'G';
               3 -- numeric for phone keypad (1,2,3 above, 7,8,9 below);
               4 -- phone keypad (3) combined with MSDOS compatibility (2);
              -1 -- alphabetic movement but 'z' swapped with 'y'.  [0]
packorder     a list of default symbols for kinds of objects that gives the
              order in which your pack will be displayed  [")[%?+!=/(*`0_]
              (If you specify only some kinds of items, the others from the
              default order will be appended to the end.)
paranoid_confirmation  space separated list of situations where alternate
              prompting is desired  [paranoid_confirmation:pray]
              Confirm -- when requiring yes, also require no to reject
              quit    -- yes vs y to confirm quitting or to enter explore mode
              die     -- yes vs y to confirm dying (for explore or debug mode)
              bones   -- yes vs y to confirm saving bones data in debug mode
              attack  -- yes vs y to confirm attacking a peaceful monster
              pray    -- y to confirm an attempt to pray; on by default
              Remove  -- always pick from inventory for 'R' and 'T' even when
              wearing just one applicable item to remove or take off
pickup_burden when you pick up an item that exceeds this encumberance
              level (Unencumbered, Burdened, streSsed, straiNed, overTaxed,
              or overLoaded), you will be asked if you want to continue. [S]
pickup_types  a list of default symbols for kinds of objects to autopickup
              when that option is on  [all]
pile_limit    for feedback when walking across floor objects, threshold at
              which "there are many objects here" is displayed instead of
              listing the objects.  (0 means "always list objects.")  [5]
runmode       controls how often the map window is updated when performing
              multi-step movement (various running modes or travel command):
              teleport -- don't update map until movement stops;
              run      -- periodically update map (interval is seven steps);
              walk     -- update map after every step;
              crawl    -- like walk, but delay after making each step.
              (This only affects screen display, not actual movement.)  [run]
scores        the parts of the score list you wish to see when the game ends
              You choose a combination of top scores, scores around the top
              scores, and all of your own scores.  [!own/3 top/2 around]
suppress_alert disable various version-specific warnings about changes
              in game play or the user interface, such as notification given
              for the 'Q' command that quitting is now done via #quit
              (e.g., use suppress_alert:3.3.1 to stop that and any other
              notifications added in that version or earlier) default: [(none)]

Compound options which may be set only on startup are:

align      Your starting alignment (align:lawful, align:neutral,
           or align:chaotic).  You may specify just the first letter.  [RANDOM]
catname    the name of your first cat  [NONE]
dogname    the name of your first dog  [NONE]
dungeon    a list of symbols to be used in place of the default ones for
           drawing the dungeon.
           The symbols are subjected to a fair amount of processing, so
           that you can use C-style escapes such as \n or \081 as well as
           indicate control characters by ^x or meta characters by \Mx.
           As usual, \ can force the next character to be taken literally.
           Since many of the default symbols are overloaded, they are
           given here by name instead of symbol, with some added notes:
           stone                               (solid rock, normally ' ')
           vwall hwall tlcorn trcorn blcorn brcorn      (room boundaries)
           crwall tuwall tdwall tlwall trwall (wallified maze characters)
           nodoor vodoor hodoor      (no, vertical, horizontal open door)
           vcdoor hcdoor               (vertical, horizontal closed door)
           ironbars tree room darkcorr litcorr
           upstair dnstair upladder dnladder
           altar grave throne sink fountain pool ice lava
           vodbridge hodbridge     (vertical, horizontal open drawbridge)
           vcdbridge hcdbridge   (vertical, horizontal closed drawbridge)
           air cloud water
           default:  \ |--------||.-|++##.##<><>_\\#{}.}..##\ #}
effects    like dungeon, but for special effects symbols
           vbeam hbeam lslant rslant                  (generic zap beams)
           digbeam flashbeam      (special beams for digging and cameras)
           boomleft boomright                                (boomerangs)
           ss1 ss2 ss3 ss4                           (shielding sequence)
           sw_topl, sw_topm, sw_topr,                  (swallow, top row)
           sw_midl, sw_midr,            (swallow, middle row [no center])
           sw_botl, sw_botm, sw_botr                (swallow, bottom row)
           extl extm extr                      (explosion matrix top row)
           exml exmm exmr                   (explosion matrix middle row)
           exbl exbm exbr                   (explosion matrix bottom row)
           default:  |-\\/*!)(0#@*/-\\||\\-//-\\|\ |\\-/
gender     Your starting gender (gender:male or gender:female).
           You may specify just the first letter.  Although you can
           still denote your gender using the "male" and "female"
           options, the "gender" option will take precedence.  [RANDOM]
horsename  the name of your first horse  [NONE]
menu_*     create single character accelerators for menu commands.  Below
           is a list of all commands.  Each is followed by a list of window-
           ports that implement them:  'x' is X11, 't' is tty, 'g' is Gem,
           'a' is Amiga.
           menu_deselect_all  deselect all items in a menu [-](gxta)
           menu_deselect_page deselect all items on this page of a menu [\](gta)
           menu_first_page    jump to the first page in a menu [^](gta)
           menu_invert_all    invert all items in a menu [@](gxta)
           menu_invert_page   invert all items on this page of a menu [~](gta)
           menu_last_page     jump to the last page in a menu [|](gta)
           menu_next_page     goto the next menu page [>](gta)
           menu_previous_page goto the previous menu page [<](gta)
           menu_search        search for a menu item [:](gxa)
           menu_select_all    select all items in a menu [.](gxta)
           menu_select_page   select all items on this page of a menu [,](gta)
monsters   like dungeon, but for monster symbols
           default:  abcdefghijklmnopqrstuvwxyz
                     ABCDEFGHIJKLMNOPQRSTUVWXYZ@\ \\&;:~]
msghistory number of top line messages to save [20]
name       the name of your character  [obtained by asking the system or
           the player]
objects    like dungeon, but for object symbols
           default:  ])[="(%!?+/$*`0_.
pettype    your preferred type of pet (cat or dog), if your character
           class uses both types; or none for no pet  [RANDOM]
playmode   normal play or non-scoring explore mode or debug mode  [normal]
race       Your starting race (e.g., race:Human, race:Elf).  [RANDOM]
role       Your starting role (e.g., role:Barbarian, role:Valk).
           Although you can specify just the first letter(s), it will
           choose only the first role it finds that matches; thus, it
           is recommended that you spell out as much of the role name
           as possible.  You can also still denote your role by
           appending it to the "name" option (e.g., name:Vic-V), but the
           "role" option will take precedence.  [RANDOM]
traps      like dungeon, but for trap symbols
           arrow_trap dart_trap falling_rock_trap squeaky_board
           bear_trap land_mine rolling_boulder_trap sleeping_gas_trap
           rust_trap fire_trap pit spiked_pit hole trap_door
           teleportation_trap level_teleporter magic_portal web statue_trap
           magic_trap anti_magic_trap polymorph_trap
           default:  ^^^^^^^^^^^^^^^^^"^^^^

windowtype windowing system to be used  [depends on operating system]

Compound option if TTY_GRAPHICS was set at compile time:
msg_window the type of message window to use:
           single      -- One message at a time
           full        -- Full window with all saved top line messages
           reverse     -- Same as full, but messages printed most-recent-first
           combination -- Two single messages, then as full
           default:  single

Some sample options lists are:
!autopickup,!tombstone,name:Gandalf,scores:own/3 top/2 around
female,nonews,dogname:Rover,dungeon: |--------||.-|++.##<><>_\\#{}.}..## #}
rest_on_space,!verbose,menustyle:traditional
